Guller S, Bulletti C, Biener A, Gurpide E
J Steroid Biochem. 1984 Apr;20(4B):975-9. doi: 10.1016/0022-4731(84)90007-4.
Published results from in vivo experiments carried out in Rhesus monkeys and from in vitro perfusions of human term placentas have indicated that placental estradiol (E2) is preferentially released towards the mother whereas estrone (E1) is about evenly distributed between fetal and maternal circulation. In order to examine the distribution of estriol, relative to that of E1 and E2, we have now prepared [3H]16-hydroxyandrostenedione by incubation of [6,7-3H]androstenedione with Streptomyces roseochromogenus and perfused placental cotyledons with mixtures of these two labeled precursors. Measurement of the concentrations of tritiated E1, E2 and E3 in the maternal and fetal perfusates, flowing at approx 10 and 5 ml/min, respectively, indicated that the distribution of E3 is different from that of E2 and resembles the distribution of E1. The simple perfusion system being used shows differences in the distribution of various estrogens between fetal and maternal perfusates which may reflect the in vivo situation and offers the opportunity for experimental examination of various explanations for these differences, e.g. existence of specific carrier systems in the syncytial membranes, specific binding of the estrogens to secreted placental proteins, and actions of placental and decidual 17 beta-hydroxysteroid dehydrogenases.
在恒河猴身上进行的体内实验以及对人类足月胎盘的体外灌注实验所公布的结果表明，胎盘雌二醇（E2）优先向母体释放，而雌酮（E1）在胎儿和母体循环之间的分布大致均匀。为了研究雌三醇（E3）相对于E1和E2的分布情况，我们现在通过将[6,7-³H]雄烯二酮与玫瑰产色链霉菌一起孵育制备了[³H]16-羟基雄烯二酮，并用这两种标记前体的混合物灌注胎盘小叶。分别以约10毫升/分钟和5毫升/分钟的流速测量母体和胎儿灌注液中氚标记的E1、E2和E3的浓度，结果表明E3的分布与E2不同，类似于E1的分布。所使用的简单灌注系统显示出胎儿和母体灌注液中各种雌激素分布的差异，这可能反映了体内情况，并为对这些差异的各种解释进行实验研究提供了机会，例如合体细胞膜中特定载体系统的存在、雌激素与分泌的胎盘蛋白的特异性结合，以及胎盘和蜕膜17β-羟基类固醇脱氢酶的作用。
